Method and batch or mixture for making illuminating-glass.



UNITED STATES PATENT oFFIcE.

I JAMES MEARA, 0F PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO GILL 8;

COMPANY, INCORPORATED, 0F PHILADELPHIA, PENNSYLVANIA, A CORPO- RATION OFPENNSYLVANIA.

METHOD AND BATCH on MIXTURE FOR- MAKING ILLUMINA'rI'Ne-eLass' NoDrawing.

To all whom it may concern Be it known thatI, JAMEs O. MEARA, a citizen.of the United States, residing in the city and county of Philadelphia,State of- Pennsylvania, have invented a new and useful Method and Batchor Mixture for Making Illuminating-Glass, of which ,the following is aspecification.

/ In the manufacture of glass for illuminating purposes, such aselectric and other similar shades and globes, it is desirable to employa process and batch which will produce a glass having a snow whlteappearance and which will be translucent to a high degree, and will, atthe same time, be not clear, and adapted to transmit light without theyellow or reddish color, known as fire, the glass in these respectsdistlnguishing from the well known opal glasses, whlch are eithersubstantially opaque and known as milk glass or are to some degreetranslucent, in which case the coloring known in this art as fire isalways noticeable when light is observed through the glass.

My invention further consists of a novel process and batch, which willproduce a glass having a white lummous appearance when. transmittinglight, with such light diffused in a manner pleasing and restful to theeyes, the glass being subject to a minimum amount of breakage upon theapplication of heat, as well as a minimum loss of illuminating power,while the so-called specks or bubbles heretofore existing in glass ofthis general character, wherein a fluorin compound or fluorid isemployed, are substantially obliterated or eliminated in my process andbatch. 7

In carrying out my invention, 1 first take a batch or mixture,thepreferred ingredients being hereinafter particularly pointed pletetransparency and the obliteration of the specks or .bubbles from theglass, the glass tending to return to its colorless crystal stage, ifthe operation is continued too long, but I prefer to continue the fusingor Specification of Letters Patent.

Patented Jan. 4, 1916.

Application filed September 19, 1914. Serial No. 862,472.

heating operation until the obliteration of said specks is nearlycompleted.

In practice, I have found that good re sults are obtained in a furnaceworking at a temperature of approximately between 2500 and 3000 degreesF. andthe length of time oxid of antimony, 1%,- lbs.; common salt, 1lbs; saltcake -(crude sodium sulfate), 1 lbs; crystallized Glaubersalts, 2 lbs; gyp sum, 1% lbs. Said ingredients are fused in anysuitable manner and form, when so combined, a white translucent glasswhich transmits, when formed into a sheet, globe or shade, light of awhite color'and' free from yellow, red or opalescent rays.

The proportions of the ingredients of the, mixture may be changed, ifdesired or re quired, according to the use of the glass and itspurposes, but for the manufacture of globes or shades for lamps,substantially the above formula of proportions has been proved to bemost satisfactory.

I desire to call special attention that in my novel foregoing processand batch, I entirely dispense with the use of a fluorid or a fluorincompound, as has been heretofore employed, and preferably employ theforegoing ingredients, whose relative proportions may vary somewhat,depending upon the variations in the basic or foundation glass. batchcomposed of the foregoing ingredients, so that the duration of operationand the degree of heat may be regulated so as to substantiallyobliterate or eliminate the so-called specks or bubbles, but I do notdesire to be limited to any exact duration of operation or to any exactdegree of heat as this may be modified or compensated for by variationsin the mixture or the length of time of the operation, as will beapparent to those skilled in this art.

.I am aware of the reissued patent to Mac beth, No. 13,766, granted July7th, 1914, and

my present invention is clearly difierenlbs; borax, 6 lbs; oxid ofarsenic,-3 lbs; I

1 preferably manipulate the glass or fiuorin'compound, and no ingredientthe I have deequivalent. thereof, as is evident.

It willnow be apparent that vised a novel and useful method and batch ormixture for making illuminating glass, which embodies the features'ofadvantage enumerated as desirable in the statement of Letters Patent, is2O 1. The hereindescribed method of manufacturing illuminating glass,which consists in fusing together a foundation mixture capable of makingsubstantially colorless clear glass, said mixture comprisingsand,alumina, oxid of lead, silex, soda, borax, oxid of arsenic, oxid ofantimony, common salt, salt cake, crystallized Grlauber salts andgypsum, and the heating operation being stopped at such a period thatthe specks in I the glass are substantially eliminated.

2. The hereindescribed method of manufacturing illuminating glass, whichconsists infusing together a foundation mixture capable of makingsubstantially colorless clear glass, said mixture comprising sand,alumina, oxid of lead, silex, soda, borax, oxid of arsenic, oxid ofantimony, common salt, salt cake, crystallized Glauber salts and gypsum,and the heating operation being stopped before the glass returns to aclear glass stage and at such a period that the specks in the glass aresubstantially eliminated. v

3. The hereindescribed mixture for manufacturing illuminating glass,composed of sand, alumina, oxid of lead, silex, soda, borax, oxid ofarsenic, oxid of antimony, common salt, salt cake, crystallized Glaubersalts and gypsum, fused together.

4:. The hereindescribed mixture for manufacturing illuminating glass,composed of sand, lbs.; alumina, 30 lbs; oxid of lead, 22 lbs. ;.silex,'12 lbs.; soda, 37 lbs; borax, 6 lbs. oxid of arsenic, 3 lbs. oxid ofantimony, 1;; lbs; common salt, 1% lbs; salt cake, 1?; lbs.;crystallized Glauber salts, 2 lbs; and gypsum, 1% lbs., fused together.

JAMES o. MEARA.

Witnesses JOHN DUNPHY, BRYAN J. TANSEY.

